LONG-RANGE DIAGONAL ADIABATIC CORRECTIONS FOR THE GROUND MOLECULAR-STATE OF ALKALI-METAL DIMERS

We study long-range diagonal adiabatic corrections to the interaction potentials of the ground state of homonuclear alkali-metal dimers. We show that in the long-range limit the diagonal adiabatic matrix elemen ts may be expressed as a series of inverse powers of the internuclear distance. Each of the nonzero coefficients of this expansion is a mass -dependent correction term to the dispersion coefficients. They are co mputed by using a complex integral representation, that transforms the molecular problem into an atomic one. Numerical results are presented .